1. Field
The following description relates to a multicast and broadcasting service (MBS) for a mobile IPTV service, and more particularly, to a method of operating a terminal as an amplified and forwarding repeater in order to improve a service quality in the MBS for the mobile IPTV.
2. Description of the Related Art
There has been much interest in a point to multipoint service for providing a plurality of users with the same contents on a network through one link, that is, a multicast broadcast service (referred to as “MBS”, hereinafter).
In a broadband wireless communication system based on Institute of Electrical and Electronics Engineers (IEEE) 802.16d/e or WIMAX standard, the MBS is a service that provides a number of subscribers with the same data.
Such an MBS can generally be divided into a multicast service in which a user dynamically joins and leaves an IP session and a broadcast service in which multicast contents are always transmitted regardless of users.
Such an MBS should transmit the same MBS contents to a number of terminals using the same multicast CID (referred to as “MCID”, hereinafter).
Further, since base stations (BSs) in an MBS_zone should support macro diversity, there should not be difference between transmission times. Further, data should be exchanged between a BS and an access service network (ASN).
The MBS network can identify a multicast and broadcast service zone. That is, an MBS_zone is used to indicate a broadcast and multicast service flow available zone. A BS broadcasts MBS_zone information using a downlink channel descriptor (DCD) message. That is, the MBS_zone is regarded as the same BS group to transmit contents.
Such MBS service is divided into a single-BS access and a multi-BS access according to a service access method of a mobile terminal. The single-BS access method is a method where a mobile terminal receives an MBS from one BS in which the mobile terminal is registered, and the multi-BS access is a method where a mobile terminal receives an MBS from two or more BSs at the same time.
In order to provide a high quality mobile IPTV service, a transmission quality is secured in an access network. While a transmission quality is improved by constructing an MBS network and minimizing interference in Mobile WiMAX and 3GPP/LTE, in addition to interference between the MBS_zones, which reduces the transmission quality, a wireless environment is deteriorated due to the effects such as radio wave propagation loss and fading according to a geographical condition such as a building even in the MBS_zone, which limits an improvement of the transmission quality.
A method for improving a reception signal quality of a terminal in a deteriorated wireless environment using a repeater that is receiving an MBS service, thereby providing a high quality broadcasting service, is needed.